6
Speed change (Fig. 2)
The revolutions and blows per minute can be adjusted
just by turning the adjusting dial. The dial is marked 1
(lowest speed) to 5 (full speed).
Refer to the table below for the relationship between the
number settings on the adjusting dial and the revolutions/
blows per minute.
CAUTION:
• If the tool is operated continuously at low speeds for a
long time, the motor will get overloaded, resulting in
tool malfunction.
• The speed adjusting dial can be turned only as far as 5
and back to 1. Do not force it past 5 or 1, or the speed
adjusting function may no longer work.
ASSEMBLY
CAUTION:
• Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
Side grip (auxiliary handle)
(Fig. 3)
For maximum control and safer operation, always use the
side grip with this tool. The side grip swings around to
either side, allowing easy handling of the tool in any posi-
tion. Loosen the side grip by turning it counterclockwise,
swing it to the desired position and then tighten it by turn-
ing clockwise.
Bit grease (optional accessory)
Coat the bit shank head beforehand with a small amount
of bit grease (about 0.5 – 1 g; 0.02 – 0.04 oz.). This
chuck lubrication assures smooth action and longer ser-
vice life.
Installing or removing the bit (Fig. 4)
Pivot the tool retainer to the side. (If it is difficult to move
the tool retainer with your thumbs, tap it with a hammer.)
Insert the bit into the tool barrel as far as it will go. Return
the tool retainer to its original position to secure the bit.
To remove the bit, follow the installation procedure in
reverse.
Depth gauge (Fig. 5)
The depth gauge is convenient for drilling holes of uni-
form depth. Loosen the clamp screw and adjust the
depth gauge to the desired depth. After adjusting, tighten
the clamp screw firmly.
OPERATION
CAUTION:
• Always use the side grip (auxiliary handle) and firmly
hold the tool by both side grip and switch handle during
operations.
Hammer drilling operation (Fig. 6)
Position the bit at the desired location for the hole, then
pull the switch trigger. Do not force the tool. Light pres-
sure gives best results. Keep the tool in position and pre-
vent it from slipping away from the hole.
Do not apply more pressure when the hole becomes
clogged with chips or particles. Instead, run the tool at an
idle, then remove the bit partially from the hole. By
repeating this several times, the hole will be cleaned out
and normal drilling may be resumed.
CAUTION:
• When the bit begins to break through concrete or if the
bit strikes reinforcing rods embedded in concrete, the
tool may react dangerously. Maintain good balance and
safe footing while holding the tool firmly with both
hands to prevent dangerous reaction.
Blow-out bulb (optional accessory) (Fig. 7)
After drilling the hole, use the blow-out bulb to clean the
dust out of the hole.
Chipping/Scaling/Demolition (Fig. 8)
Hold the tool firmly with both hands. Turn the tool on and
apply slight pressure on the tool so that the tool will not
bounce around, uncontrolled. Pressing very hard on the
tool will not increase the efficiency.
Core bit (optional accessory)
When using the center bit
Screw the core bit on the adapter. Install the adapter with
the core bit in the tool in the same manner as a drill bit.
(Fig. 9)
Install the center bit. (Fig. 10)
Rest the core bit on the concrete and turn the tool on.
Once the core bit has cut a shallow groove into the con-
crete, remove the center bit. Then resume drilling.
(Fig. 11)
To remove the core bit, follow the procedures 1 or 2.
1.
Rotate the change lever to the
position. Then
rest the core bit on the concrete and turn the tool on.
The core bit will come loose from the hammering
action. (Fig. 12)
2.
Hold the adapter with the wrench, insert the rod
(optional accessory) into the hole in the core bit and
tap with a hammer to unscrew. (Fig. 13)
When not using the center bit
Screw the core bit on the adapter. Install the adapter with
the core bit in the tool in the same manner as a drill bit.
(Fig. 14)
Rotate the change lever to the
position. Rest the core
bit on the concrete and turn the tool on. Once the core bit
has cut a shallow groove into the concrete, rotate the
change lever to the
position and resume drilling.
(Fig. 15)
NOTE:
• No problem is caused even if the core bit unscrews
slightly during brief use since the core bit rotates in the
tightening direction.
To remove the core bit, follow the same removal proce-
dures covered in “When using the center bit”.
Number on
adjusting dial
Revolutions per
minute
Blows per
minute
5
460
2,600
4
420
2,400
3
350
2,000
2
270
1,500
1
230
1,300
